package com.sinry.common.log.utils;

import lombok.extern.slf4j.Slf4j;
import org.slf4j.MDC;
import org.springframework.util.StringUtils;

import javax.servlet.http.HttpServletRequest;

/**
 * @author linxinlei
 * @project sinry-cloud
 * @description ip地址工具
 * @date 2022/6/5
 **/
@Slf4j
public class IpUtils {

    public static final String REQUEST_IP = "ip";
    public static final String UNKNOWN_IP = "unknown";

    /**
     * 获取IP地址
     * <p>
     * 使用Nginx等反向代理软件， 则不能通过request.getRemoteAddr()获取IP地址
     * 如果使用了多级反向代理的话，X-Forwarded-For的值并不止一个，而是一串IP地址，X-Forwarded-For中第一个非unknown的有效IP字符串，则为真实IP地址
     */
    public static String getIpAddr(HttpServletRequest request) {
        String ip = null;
        try {
            ip = request.getHeader("x-forwarded-for");
            if (!StringUtils.hasText(ip) || UNKNOWN_IP.equalsIgnoreCase(ip)) {
                ip = request.getHeader("Proxy-Client-IP");
            }
            if (!StringUtils.hasText(ip) || ip.length() == 0 || UNKNOWN_IP.equalsIgnoreCase(ip)) {
                ip = request.getHeader("WL-Proxy-Client-IP");
            }
            if (!StringUtils.hasText(ip) || UNKNOWN_IP.equalsIgnoreCase(ip)) {
                ip = request.getHeader("HTTP_CLIENT_IP");
            }
            if (!StringUtils.hasText(ip) || UNKNOWN_IP.equalsIgnoreCase(ip)) {
                ip = request.getHeader("HTTP_X_FORWARDED_FOR");
            }
            if (!StringUtils.hasText(ip) || UNKNOWN_IP.equalsIgnoreCase(ip)) {
                ip = request.getRemoteAddr();
            }
        } catch (Exception e) {
            log.error("IPUtils ERROR ", e);
        }

        return ip;
    }

    /**
     * 将IP存入日志
     */
    public static void setLogIp(HttpServletRequest request) {
        String ipAddr = getIpAddr(request);
        MDC.put(REQUEST_IP, ipAddr);
    }

    /**
     * 从日志中获取已写入的IP
     *
     * @return  IP地址
     */
    public static String getLogIp() {
        String ip = MDC.get(REQUEST_IP);
        if (!StringUtils.hasText(ip)) {
            ip = UNKNOWN_IP;
        }
        return ip;
    }

}
